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    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        a:link{color: green}
        a:visited{ color: red}
        a:hover{color: yellow}
        a:active{color: blue}
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<body>
<a href="http://www.baidu.com">百度</a>
<a href="http://www.tedu.cn">达内</a>
<a href="http://www.qq.com">腾讯</a>
<a href="http://www.bilibili.com">哔哩哔哩</a>
</body>
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